Semiconductor elements such as switching elements or diodes are used for circuits such as switching power sources or inverters. These semiconductor elements require high breakdown voltage and low on-resistance. Herein, the breakdown voltage and the on-resistance have a trade-off relationship determined by element materials.
Up to now, with the advance of technology development, for main semiconductor elements, low on-resistance near the limit of silicon (Si) as a generally used element material is realized. For further improvement of the breakdown voltage or reduction in on-resistance, element materials are preferably changed. By using a wide-band-gap semiconductor material such as a gallium nitride (GaN)-based semiconductor material or a silicon carbide (SiC)-based semiconductor material as a switching element material, the trade-off relationship can be improved, so that the high breakdown voltage or low on-resistance of the elements can be drastically implemented.